These metrics seem to be interesting from a analytical and theoretical perspective. Has anyone found these to be of practical use?

Clearly a single sided crankarm powermeter can not generate the necessary data (ex Stages, 4iiiis). It also seems that the initial run of Powertap P1 pedals did not send this data to the head unit.

Which powermeters will allow this type of data to be generated for analysis of GPR, GPA, KI?